The present disclosure relates to an A/D converter and a semiconductor device for converting an analog output signal into a digital signal.
Conventionally, multi-element sensors such as imaging devices have been widely used. The multi-element sensor desirably has a large dynamic range, and particularly, an X-ray imaging element, an infrared imaging element, or the like is required to have a large dynamic range.
The sensor or the like is provided with an A/D conversion circuit for converting an analog signal into a digital signal. The A/D conversion circuit is not limited to a sensor or the like, and may be used in various applications.
In this regard, Japanese unexamined Patent Application publication 2011-139259 discloses an A/D conversion circuit capable of expanding a resolution by using an A/D conversion circuit having a low resolution.